Preparation method of large-size yttrium aluminum garnet (YAG) laser crystal

Abstract

The invention provides a preparation method of a large-size yttrium aluminum garnet (YAG) laser crystal. The preparation method comprises the following steps: mixing raw materials for preparing yttrium aluminum garnet with raw materials of doping elements, pressing the mixed raw materials into a cake material, and carrying out sintering to obtain a YAG polycrystalline cake material; heating the obtained YAG polycrystalline cake material to a molten state, placing the molten material in a mixed atmosphere of oxygen and inert gas for oxygen diffusion, and then carrying out liquid purification; adding a seed crystal into the molten raw materials subjected to the liquid purification, and carrying out crystal growth by a Czochralski method; and after crystal growth is finished, lifting a growncrystal to the liquid surface, and carrying out cooling to obtain the YAG laser crystal. The preparation method can be used to prepare the YAG laser crystal with high quality, the diameter of the YAGlaser crystal can reach 100 mm, the effective length can reach 200 mm, the doping concentration of crystal active ions is uniform, crystal defects are few, the core is small, the effective utilizationrate of the crystal is greatly improved, and large-size laser slabs and discs can be conveniently processed by cutting. Meanwhile, the process steps of the preparation method is simplified, and costis reduced.

Description

technical field [0001] The invention belongs to the field of crystal preparation, and relates to a method for preparing a YAG laser crystal, in particular to a method for preparing a large-size YAG laser crystal. Background technique [0002] As the most important laser crystal so far, neodymium-doped yttrium aluminum garnet (Nd:YAG) has become the most mature and mainstream laser crystal material in the world, and occupies a very important position in the field of solid-state laser applications. More than 50% of the world's solid-state lasers use neodymium-doped YAG laser crystals, and neodymium-doped YAG laser crystals are also the first choice for high-power solid-state lasers. Although the YAG laser crystal has developed rapidly and achieved a series of achievements, there are still some problems: such as small size (the domestic mainstream product specification is Ф50mm / 60mm ingot, the longest product length can only reach 200mm), product core Large size, many crystal ...

AI Technical Summary

Problems solved by technology

Although the YAG laser crystal has developed rapidly and achieved a series of achievements, there are still some problems: such as small size (the domestic mainstream product specification is Ф50mm / 60mm ingot, the longest product length can only reach 200mm), product core Large size, many crystal defects, easy crystal cracking, small residual stress, low utilization rate of ingot, etc., cannot meet the needs of high-power lasers, seriously affecting the development of high-power solid-state lasers in China

[0003] CN 101338453 A discloses a method for growing large-scale coreless YAG series laser crystals, which uses a growth device and method of resistance heating molybdenum crucible pulling method, and can only obtain 35-50mm YAG series laser crystals, and The crystal power obtained by this method is low, and most of them are used in beauty bars with low power requirements, rather than industrial high-power bars.

CN 201241194 Y discloses a laser crystal growth device by induction heating iridium crucible pulling method. This patent describes a growth device, but does not involve a specific crystal growth method, nor does it describe how large a crystal can be grown by using the device

Images